Hummingbird Migration Stopovers & Flights

Ruby-throated Hummingbirds are reaching their peak migration period across the eastern half of the United States (photos by Paul Konrad).
As hummingbirds are migrating and making crucial stopovers during September, it is interesting to learn more about the biology and energetics of how some Ruby-throated Hummingbirds prepare for long non-stop fall migration flights. During a study of Ruby-throats making a stopover in southern Alabama, one of several interesting pieces of information was discovered that permitted researchers to estimate that the “average” Ruby-throated Hummingbird has a nonstop migration flight range of about 1,320 miles.
The Alabama study found that some Ruby-throats effectively double their body mass during feeding bouts during a migration stopover, in advance of making long-distance migration flights. To study these and other topics, researcher Theodore Zenzal and his colleagues captured, banded, measured, weighed, and released 2,729 Ruby-throated Hummingbirds during 5 fall migration periods at Bon Secour National Wildlife Refuge, located on the southern tip of Alabama adjacent to the Gulf of Mexico.
After collecting weight and age data about each hummingbird they caught, the researchers used a computer program to estimate the Ruby-throats’ flight range based on birds’ body mass and wingspan. The resulting information provided their estimate that the “average” Ruby-throated Hummingbird has a flight range of about 1,320 miles. Using this method, they also predicted that older hummingbirds and males were able to travel farther than younger hummingbirds and females.
The flight ranges that researchers calculated mean that most Ruby-throats would be able to migrate directly across the Gulf of Mexico to the Yucatan Peninsula of Mexico, a distance of less than 700 miles. While it is not yet substantiated that Ruby-throated Hummingbirds migrate across the Gulf of Mexico in numbers, new methods of tracking hummingbirds should soon provide more information about that continuing question. For now, researchers believe most Ruby-throated Hummingbirds migrate around the Gulf, funneling along the coast to locations like Rockport, Texas and the Corpus Christi area, then south.

Male Ruby-throated Hummingbirds tend to migrate earlier than females in many areas, with young of the year averaging slightly later migration times. Read more







